Engines shut-down system

The term engineered safety covers the provision in the design of control systems, alarms, trips, pressure-relief devices, automatic shut-down systems, duplication of key equipment services and fire-fighting equipment, sprinkler systems and blast walls, to contain any fire or explosion. 

Functional safety engineering involves identifying specific hazardous failures whieh lead to serious consequenees (e.g., death) and then establishing maximum tolerable frequency targets for each mode of failure. Equipment whose failure contributes to eaeh of these hazards is identified and usually referred to as safety related. Examples are industrial process control systems, proeess shut down systems, rail signaling equipment, automotive controls, medical treatment equipment, etc. In other words, any equipment (with or without software) whose failure ean eontribute to a hazard is likely to be safety related. 

There are few chemical plants that are so forgiving that a control system or a safety interlock system is not required. Process engineers provide controls to assure product yield and quality and maintain safe operating conditions. This type of control system is a BPCS. The BPCS acts to alarm and moderate a high or low operating condition specified by the normal operating limits within the never exceed critical limits. The SIS is provided to shut down or otherwise place the process in a safe state if the BPCS fails to maintain safe operating conditions. A BPCS should not be used as the sole source of a process safety shutdown. 

Effective inlet air filtration is required to ensure satisfactory operation of the engine. The location of the unit determines the most appropriate filter system to use. Desert environments where a large amount of sand particles could be expected in the ambient air may use an automatic roll type of filter that allows new filter material to be rolled in front of the inlet without frequent shut-downs to change filters. Arctic or extremely cold locations may use pad type filters, snow hoods to prevent blockage, and exhaust recirculation to prevent icing. Filter assemblies for offshore marine environments may include weather louvers, demister pads, and barrier elements for salt and dirt removal. Screens may be u.sed for insect removal prior to filtration in areas with bug problems. 

The process engineer must decide which operations require spare pumps. Obviously, if a system contains only one pump and that pump fails, there is no way to transfer the fluid and the process must eventually be shut down. If a spare pump is in place the process can be continued with almost no interruption. However, the initial cost of the plant is also increased by the cost of the pump and the price of its installation. For large-capacity systems an alternative is to place two pumps that can operate at about 55%-60% of the desired capacity in parallel with each other. Then when one fails the process merely needs to be cut back until repairs can be made. 

It is the job of the process engineer to see that any new plant meets federal and state regulations. He may do this by designing a system to handle the wastes, or he may arrange for a municipality or a central processing facility to treat his wastes. In the latter case he must be careful, since if the plant processing his wastes goes on strike or is temporarily shut down he may be forced to shut down his own facilities to avoid stiff pollution fines. 

I and my son are reverse-engineering the relay that I cut the sides off of and we are going to find newer stuff that can be used for the same use as the relay and as cheap as we can. I found a guy who is 85 years old who knew what the relay fit. It operated two pumps on a 1949 Johnson-Prutte air cooling system. The relay was used to the turn on two pumps, when one would start to get hot the relay would switch the power to the other pump before the other shut down, that s the reason for the diodes in the relay. 

Inadvertently shut down of ventilation system. All agent vapor maintained under engineering controls. LIC secondary room was maintained under engineering controls. No agent release. 

Engine indicating system N/A N/A Electrical connectors are identical Cross connection could cause the wrong engine to be shut down in the case of an emergency Ensure that all connectors are keyed and properly labelled to prevent cross connection... 

The system has two operating modes ACTIVE and DORMANT. In the ACTIVE mode, aU pumps in the tanks are activated and fuel is fed from the collector tank into the engine. The transfer of fuel from the main and the wing tanks depends on the level in the coUector tank. In the DORMANT mode there is no fuel transfer and the pumps are shut down. 

The appropriate combination of inherent safety features and engineered ones should be necessary to prevent the extension of anticipated transients and also postulated accidents within the system. As an example of inherent safety features, one should mention Doppler reactivity that is effective against criticality events, which is a basis to ensure the reactor shut down function. Natural circulation is also an inherent safety feature to enhance the cooling capability of the reactor core. The nuclear energy system should be designed in such a way that severe core damage leading to the release of massive amounts of radioactive materials could be avoided. 

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